Control system.



J. L. HALL. CONTROL SYSTEM. APPLICATION I'ILED 11111112, 1911.

1,029,362, 1 I Patented June 11,112.

2 SHEETS-SHEET 1.

lnvetm: John LHaH,

J. His to'r'ne g J. L. HALL.

CONTROL SYSTEM.

APPLICATION FILED JUNE 2, 1911.

1,029,362., Patented June 11,1912.

1 1, Fig.5.

2 SHEETS-SHEBT 2.

j v gm Inventor:

John LHaH Hisofltitorneg.

mv'rn sra rne arias orie JOHN L. HALL, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

CONTROL SYSTEM.

Specification of Letters Patent.

Patented June 11 1912.

To all whom it may concern:

Be it known that I, JOHN L. HALL, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Control Systems, of which the following is a specification.

This invention relates to electromagnetic nieans for controlling electric circuits.

In one aspect my invention comprises a system of control in which a member, such as a rheostat arm for a theater dimmer or a Searchlight projector stationed at a remote point from the operator, may be automatically moved in response to the movement of the controller in the hands of the operator.

One of the objects of my invention is to provide improved means whereby the member to be operated moves in synchronism with the movement of'the controller, the arrangement being such that the construction and wiring is simplified and the operation rendered positive and etficieiit. a

In another aspect my inventlon comprlses a system of electromagnetic control embodying a plurality of differentially wound coils arranged to operateso as to effect certain. novel results'hereinafter specified. I

In the accompanying drawing in which I have illustrated my invention as embodied in concrete form, Figures 1 and 2 are circuit diagrams showingithe principlesuof electromagnetic operation involved in one aspect of my invention; and Fig. 3 shows a'remote control system for a theater dimmer embodying the principles of Figs. 1 and 2. v

Before taking up the description of my complete system of control shown in Fig. 3, I shall describe the fundamental features of the electromagnetic controller.

Referring first to Fig. 1, A and B represent two electromagnetic windings. Each of these windings has two coils a b and 0 (Z respectively. These two coils of each winding are differentially wound and connected in series, as shown, across the supply circuit Z Z; Switches 6 and f are connected in series with each of the windings A and B respectively. The two windings are connected at the juncture of the two coils by the wire 9: It is obvious that if the coil 6 has twice as many turns of the same size wire-,as the coil (1 and the winding B is wound in the same manner, that if the switch 6 is closed, current will pass from the line Z through the coil a and will then divide, half the current goingthrough the coil Z) and half through 0011 d. The coil Z) now carrieshalf of the current of coil a but as Z) has twice as many turns as a, the ampere turns of coils a andb will be 'the same. The two coils a and b being differentially wound, counteract each other, therefore, so far as they would tend to operate a core, and the winding as a whole will therefore be inactive for thispurpose. Winding B, on'the other hand,- becomes active since the coil (Z only is energized. -It is obvious that, when switch 6 is opened and closed the winding B will be energized and deenergized and any core connected therewith will be operated. In a similar manner, if the switch f is opened and closed, the winding .A will become inactive and active, respectively, by reason of'the energization of the coil 6 and this, too, will operate any movable-core that may be associated therewith. If now switches e and f.

are both closed,-windings A and B will both be actively energized, since both windings are connected across the line, the connection being made between equipotential points. If while one of'these switches is closed, as, for instance, f, the other switch a is opened and closed, the winding B will beoperatively energized and deenergized, the winding A being all the time energized. In the same way, of the switch e is keptpermanently closed and the switch f is opened and closed the winding A will be operatively energized and deenergized, while the wind ing B will remain operatively energized.

Referring now to Fig. 2, it will be seen that I have applied the same principles to four electromagnets A, B, C and D, connection 9 being made as before between the windings A and B, while the connection 71 is made in a similar manner between the windings G and D. In this case ,the'swi tch 71, which I have shown as a rotary controller in the ofi'fposition, is theequivalent of the switch 6 in Fig. l. The switch arm 7' cooperating with the contact ]a is the equivalent of the switch f in Fig. '1. Ina similar manner, the controller m is provided for winding C and a contact n cotiperatingavith the switch arm y' constitutes a switch for the winding D. The two windings A and C are connected together to one side of the line through wire 0 and windings D and B are [connected through the same side of, the line through wire p. Controllers m and i are connected to line Z through wire (1, while the 1 switch member j is connected with the same side of the line through wire 1". Assuming now that the controller 2' is turned from the position shown in the drawing so as to complete a circuit through the controller, the parts otherwise being in the position shown in Fig. 2, the operation will be as follows: A circuit is completed from line Z through the controller 1', through coil a of winding A, and then through the coils b and ti in parallel through wires 0 and g) to line Z. Since the current divides through the wire g the ampere turns of the two coils a and 7) will be equal. The .coils being differentially wound, the winding A will not be operatively energized, while the coil d of the winding B, being energized, will operate any core which might be. associated therewith. -At the same time controller m being in the off position. the coil 0 of winding C will be energized to operate a core while the two coils of winding D being equally and oppositely energized, this winding will not operate its armature. The result is that windings B and C will be operatively energized. If now the switch is.moved to the opposite position so as to engage the contact in the winding B will still remain operatively energized since the two coils are connected directly across the line, while the'two coils of winding A will also be connected across the line. The winding A. will now be energized while the winding C will be denergized. If, therefore, the switch arm j is moved back and forth between the contacts n and Z' the windings A and C will be alternately energized, while the winding B will remain energized. In a similar manner, if the controller m is moved to closed circuit position while the controller 2' is left in the open circuit position the winding D will be operatively energized while the windings A and C will be alternately energized by the vibration of the member j between the contacts n and .75. The result is that with either one of the controllers i and m moved to closed position and the switch arm :5 vibrating between these contacts, the windings C and A will be alternately energized, while either D or B 'will remain energized, depending upon which controller is moved.

The mode of operation of the magnets just described is the mode of operation of the magnets in the arrangement shown in Fig. 3. Referring to this figure, it will be seen that I have shown the member to be controlled as a rheostat, such as is commonly known as a theater dimmer, for controlling the lamps 10 connected with the supply circuit. This rheostat consists of a disk 11 3 having an arm 12 mounted thereon so as to cooperate with studs 13 forming the termi open by spring 21 and is arranged to be closed by a magnet 22 when the latter is energized. The circuit of the magnet 22 5 passes through a limit switch 23 which is moved to the closed position by spring 24 and is opened by a pin 25 on the disk. The

clutch 2O is-similarly operated by electromagnet 26, the circuit likewise passing through limit switch 27 which is also opened by the pin 2). Cam wheel 28 is mounted on the shaft of the pinion 16 so as to'operate a switch consisting of a bell crank lever having a roller at one end engaging the face of the cam while the other end vibrates between the contacts 29 and 30. The switch is held against the cam asshown by the spring 31. The arrangement is such that as the cam 28 is rotated an amount equal to a step of the rheostat, the switch arm will move to the opposite position so that the switch vibrates back and forth as the rheostat arm moves step by step. 32 and 33 are electromagnetic switches having the windings B and corresponding to the windings in Fig. 2.

The controller for controlling the movement of the rheostat disk 11 comprises an operating operate one or the other of the controller rings 35 and 36, depending upon the direction of rotation of the handle. The arhandle 34 which is adapted to rangement is such that when the controlling Y handle 34 is moved in one direction the controller'35 will be mov ed against abias caused by the tension of a spring 53, while when the handle is moved in the opposite direction the contact ring 36 ismoved in the opposite direction against the bias caused by a similarly arranged spring. The arrangement is such that as the handle is turned by the operator in either direction, the controller ring which has been operated thereby is turned in the opposite direction so as to bring it back toward the off position, this movement being under the control of the switch 30. The mechanism whereby shaft 41 is mounted upon a shaft 48 extending through the sleeves 37 and 39. The sleeve 39 carries an escapement disk 44 adapted to be engaged by two pawls 45 controlled by magnets A and C. When the magnet A is operatively energized its cooperating pawl 45 will be attracted againstthe tension of the spring 46 so as to release the disk and allow the sleeve to rotate half a revolution until it engages the other pawl. Similarly, when the magnet- G is operatively energized its coiiperating pawl will be attracted and allow the. sleeve to rotate half a revolution. Mounted'upon the shaft 43 is a pinion 47 meshing with the spur gear 48 secured to the shaft 49. Upon this shaft isa finger. 50 arranged to rotate either one of the contact rings 35 or 36 in the direction of rotation of the finger. This is accomplished by having a pin 51 mounted on the ring 35 and a similar pin 52 mounted on the ring 36. so that when the finger 50 is moved in one direction it engages the pin 51 and rotates the ring 35 against the tension of the spring 53, while if the shaft 49 is rotated in the opposite direction, the finger 50 will engage the pin 52 and rotate the ring 36 against the tension of the spring 54. Mounted upon the sleeve 39 is a pinion 55 engaging with a spur gear 56 for operating a pointer over the dial arranged to indicate the movement of the handle. This indicator is calibrated so that the position of the pointer will indicate the position of the rheostatarm.

The operation of my device as a whole is as follows: Assuming the'switch 57 to be closed and it is desired to actuate the rheostat, the handle 34 is rotated in a clockwise direction. .The rotation of the handle 34 causes thestnb shaft 41 carrying the gears 42 to rotate, since the sleeve 39 is held stationary by the pawls 45. The shaft 43 being driven causes the shaft 49 to rotate, which in turn causes the contact ring 36 to be r0- tated in acounterclockwise direction against the tension .of its spring. As soon as this ring is rotated away from the off position a circuit is completed from the line Z. through wire 58, wire 59, through one. of the coils a of winding A. thence through difi'erential coil Z) of winding A and wire 60 in parallel with coil (Z and wire (31. to line l. v This causes the winding B to actuate the electromagnetic switch At the same time a circuit is closed from line I through wire 62, through contact 30, thence through one of the coils of'winding D and then through the other coil and wire (31 in parallel with one of the coils of winding C and wire 60 to line Z. This causes the electromagnet (l to operate its pawl and allow the sleeve 39 to rotate half a revolution. The closing of the electromagnetic switch 33 energizes the clutch magnet 26 which actuates the clutch 20, the circuit being through switch 57,

carry the arm 12 over the studs 14 to insert resistance in the lamp circuit. As the arm 12 moves a certain distance, as, for instance, one step to the next stud, the cam 28 moves its switch so as to engage contact'29. The

closing of the circuit at 29 has the effect, as above stated, of operatively energizing the Winding A and deenergizing the winding C,

while the electromagnetic switch 33 remains closed. Asthe rheostat arm moves forward over its studs the windings A and C alternately operate the escapement mechanism so as to permit the sleeve 39 to vrotate half a revolution at. each step inresponse to the bias of'the spring 54. This has the effect of allowing-the beveled gear 40 of the differential mechanism to turn, the net result be ing that the shaft v43 will remain substan-- tially stationary, while the handle 34 is being turned.v This causes therheostatarm 12. to

move in synchronism with the movement of the handle 34. This movement continues until the circuit of the clutch magnet 26 is opened by the pin 25 engaging the limit switch 27. In a similar manner, if the arm 34 is rotated in the opposite direction the contact ring'35 will be rotated against its bias and the magnetic switch 32 will be operated. Similarly the clutch magnet 22 will be energized so as to cause the -rheostat arm to be rotated in the opposite direction and the two'windings A and C will be alternately energized to cause a synchronizing movement. It will thus be seen that the-operator, who may be stationed at a remote point, can cause the rheostat to move to any desired position, either backward or forward, and the position of the rheostat would always be apparent to him from the indicator. Moreover, the operator may set thc operating mechanism by turning the handle 34 to the position which he wishes the rheostat arm to assume and, by leaving the switch 57 open, the rheostat will not be moved until the operator. wishes. He can thus set one or a number of these devices in advance and at the proper moment by closing the switch 57the rheostat. will be moved to the position to which it is set. This feature is particularly desirable in theaters where a large number of dimmers are to be operated within a very short time, there being an interval in which theoperator may prepare for the operation. The arrangement whereby this is accomplished is simple, especially as .to the wiring. and the operation is positive and reliable.

jVhile I have described my invention as embodied in concrete form and as operating in a specific manner, in accordance with the patent statutes. it should be understood that I do not limit my invention thereto,

since various modifications thereof will suggest themselves to those skilled in the art without departing from the spirit of my invention, the scope of which is set forth in the annexed claims.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, is,-

1. The combination with an electric inotor, of a member driven thereby, and means for controlling the operation of said member comprising a circuit controller biased to otl position, means for moving the controller against the bias, electroresponsive means for causing the controller to move a predetermined amount in response to its bias upon a corresponding movement of said member, and a switch for controlling the circuit of said elcctrorcsponsive means.

The combination with an electric motor, of a member driven thereby, means for cont-rolling the operation of said member comprising a circuit controller biased to off position, means for moving the controller against the bias, an electroresponsive device for causingthe controller to return to the oil position in response to its bias with a step by step movement corresponding to the movement of said member and a switch for controlling the circuit of said electrorcsponsive device.

3. The combination with an electric motor, of a member driven thereby and means for controlling the operation of said member comprising a circuit controller biased to oil' position, means for moving the controller against the bias," electroresponsive means controlled by the "movement of said member for causing said controller to return to off position with a step by step movement in response to its bias, and a switch for control ling the circuit ct said elect-roresponsive means.

4. The combination with an electric motor, of a member driven thereby. and means for contro ling the operation of said member comprising a circuit controller biased to otl position. means for moving the controller against the bias. a pair of elcctromagnets, and means controlled by the movement of said member for causing the said magnets to be alternately energized to cause the controllcr to return to the off position with a step by step movement in response to its bias.

5. The combination with an electric mo tor, of a member driven thereby. and means for controlling the operation of said member comprising a circuit controller biased to otl position and movable in opposite directions against said bias, means for moving the controller against the bias. electroresponsive means t'or causing the. controller to move a predetcrmined amount in response to its bias upon a corresponding movement of said member in a corresponding direction,

and a switch for controlling the circuit of said clcctroresponsivc means.

" tor, of a member driven thereby, means for controlling the operation of said member comprising a circuit controller, means for moving the same in one direction, electroresponsive means for causing the controller to move with a predetermined movement in the opposite direction upon a corresponding movement of said member, and a switch for controlling the circuitof said electroresponsive means.

T. The combination with an electric motor, of a member driven thereby, and means for controlling the operation of said member comprising two circuit controllers biased to an oil? position, one movable in each direction for opposite directions of movementof said member, means for moving the controller against the bias, a pair of electromagnetic devices, a pair of electromagnetic switches one for causing rotation of said member in each direction, and connections whereby one of said switches is closed and said electromagnetic devices are then oper ated alternately under the control of the movable member to cause the controller to return to the off position.

8. The combination with an electric motor, of a member driven thereby, a manually operated controller and means for causing the member to move in synchronism with said controller comprising two pairs of electromagnetic devices each having differential coils connected in series, a connection between each pair of magnets at the juncture of their coils, a switch operated by the movement of said member for connecting one magnet of each pair across the line alternately, and connections whereby the other pair of electromagnets are connected across the line through the controller, the differential coils being so proportioned that. their am: pere turns are equal when the current divides through the said connection.

9. The combination with an electric motor, of a mcmbdr driven thereby, a manually operated controller, and means for causing the member to move in synchronism with said controller comprising an electromagnetic circuit closer and electromagnetically controlled means for causing the controller to return to oil position, said magnets having their actuating windings connected-in parallel, each winding consisting of two differentially wound coils connected in series, a connection between the windings at the juncture of the coils, a switch in series with one winding arranged to be opened and closed by the movement of said member, and connections for closing the circuit of the other winding through said controller, the differential coils of-each winding being so proportioned that their ampere turns are equal when the current divides through said connection.

10. The combination with an electric motor, of a member driven thereby, means for controlling the operation of said member comprising a circuit controller biased to off position, means for moving the controller against the bias, electroresponsivemeans for causing said controller to return to off position in response to its bias, said latter means comprising two'pair of electromagnetic devices each having differential coils connected in series, a connection between each pair of magnets at the juncture of their coils, a switch operated by the movement of said member for connecting one magnet of each pair across the line alternately and connections whereby the other pair of electromagnets are connected across the line through the controller, the differential coils being so proportioned that their ampere turns are equal when the current divides through the said connections. v

11. The combination with an electric motor, of a member driven thereby and a manually operated controller having a switch rotatable from an ofi position against a bias in each direction for opposite directions of rotation of said member, and means for causing the member to move in synchronism with said controller comprising two electromagnetic circuit closers each having diiferential actuating coils connected in series, a switch operated by the movement of said member for connecting said windings across the line alternately, electrically controlled means for causing the controller to return to the off position step by step, said means including two magnets each having ditferential coils in series connected in parallel across the line one through each switch of the controller, and a connection between the juncture of the windings of each circuit closer and the juncture of the windings of the magnet the differential coils being so proportioned that their ampere turns are equal when the current divides through said connection.

.12. The combination with an electric inotor, of a member driven thereby, a manually operated controller having a switch for each direction of rotation, and means for causing the member to move in syncronism with said controller comprising two electromagnetic circuit closers each having differential actuating coils connected in series, a switch operated by the movement of said member for connecting said windings across the line alternately and electrically controlled means for causing the controller to return to off position, said means includture of the windings of each circuit closer and the juncture of the windings of a magnet, the differential coils being so proportioned that their ampere turns are equal when the current divides through the said connection;

13. In combination, two pairs of electro magnetic devices each having difierentially wound coils in series, a connection between the two windings of a pair at the juncture of the .coils thereof, a switch in the circuit of one winding of each pair and a second switch common to the other two windings so as to connect either across the line, the differential coils being so proportioned that their ampere turns are equal when the current divides through said connection.

14. 111 combination, two pairs of electromagnetic devices each having differentially wound coils in series, one coil havin twice as many turns as the other, a connectlon between the two windings of a pair at the juncture of the coils thereof, a switch in the circuit of one winding of each pair and a second switch common to the other two ing two magnets each having diiterential windings so as to connect either across the line.

15. In combination, a pair of electromagnetic devices having difl'erentiallv wound coils in series, a movable member for each device, a switch for connecting each winding across a supply circuit, and a connection between the two windings at the juncture of their coils, the difierential coils being so proportioned that their ampere turns 

